The semiconductor integrated circuit industry has experienced rapid growth in the past several decades. Technological advances in semiconductor materials and design have produced increasingly smaller and more complex circuits. These material and design advances have been made possible as the technologies related to processing and manufacturing have also undergone technical advances. In the course of semiconductor evolution, the number of interconnected devices per unit of area has increased as the size of the smallest component that can be reliably created has decreased.
Many of the technological advances in semiconductors have occurred in the field of memory devices, and some of these involve capacitive structures. Such capacitive structures include, for example, metal-oxide-semiconductor (MOS) capacitors, p-n junction capacitors and metal-insulator-metal (MIM) capacitors. In some applications, MIM capacitors can provide certain advantages over MOS and p-n junction capacitors because the frequency characteristics of MOS and p-n junction capacitors may be restricted as a result of depletion layers that form in the semiconductor electrodes. A MIM capacitor can exhibit improved frequency and temperature characteristics. Furthermore, MIM capacitors are formed in the metal interconnect layers, thereby reducing CMOS transistor process integration interactions or complications.
However, in order to couple an MIM capacitor to an interconnect line, a via is generally used to bridge an electrode of an MIM capacitor and an interconnect line. Forming such a via to bridge a conventional MIM capacitor may cause damage to at least one of the electrodes of the MIM capacitor and may in turn disadvantageously affect performance of the MIM capacitor (e.g., leakage current, undesirable frequency performance). Thus, an improved structure of an MIM capacitor may be needed.
The various features disclosed in the drawings briefly described above will become more apparent to one of skill in the art upon reading the detailed description below. Where features depicted in the various figures are common between two or more figures, the same identifying numerals have been used for clarity of description.